LUBAN LOCK LAB

THE JOINERY WORKSHOP / 01

The six-piece Luban lock.

Only one piece can move. Can you find it?

Play the 3D wooden burr puzzle and see which hidden surfaces keep the six pieces locked together.

01 / THE SPECIMEN
Isometric diagram of the six interlocked wooden bars

THE FIRST MOVE

Pick a piece. Try a slide.

Tap a wooden bar or its letter below the model, then choose an arrow. A blocked move reveals the point of contact.

FIELD NOTE / 01

How does a six-piece burr puzzle work?

The Luban lock (鲁班锁), sometimes called a Kongming lock or Chinese cross, is a wooden interlocking puzzle. In this six-piece version, pairs of bars cross at right angles. Each notch makes room for a neighboring bar. The solid shoulder beside that notch can stop the neighbor from sliding.

Try sliding a bar to see which surfaces meet. If you want the answer, open the written solution below.

Reveal the six-step Luban lock solution
  1. Slide the straight key A all the way out toward +X.
  2. Shift upright C one notch toward +Z, then slide it out toward −X.
  3. Lift crossbar E toward +Y.
  4. Shift post D one notch toward +Z, then slide it out toward +X.
  5. Lift rail B toward +Y.
  6. Slide brace F down toward −Y. Reverse the sequence to assemble.

FIELD NOTE / 02

Before you take it apart

Will this solve the wooden puzzle I own?

Compare the shapes and notches of your pieces with the model. Six-piece burr puzzles can look alike from the outside and still need different moves to come apart.

Can I play on a phone?

Drag to look around, pinch to zoom and tap a piece or its letter to select it. The arrows below the model follow the view. The dotted circle (⊙) points toward you and the crossed circle (⊗) points away.

Can I 3D-print the lock?

The geometry comes from a published STL set. We have checked the moves in the browser. If you want to print it, get the original STL files and fitting instructions.

CONTACT

Questions or feedback?

Tell us which move surprised you, or where the puzzle was hard to use.

[email protected]